This invention relates to an improved solar energy collector unit adapted for mounting on the exterior of buildings.
In recent years, increasing concern over depletion of conventional energy sources has resulted in increasing efforts to develop and utilize alternate energy sources. One result of such efforts has been the development of various solar energy collectors, designed to trap radiant energy from the sun and convert it to a more usable, distributable energy form. Such solar energy collectors are commonly mounted on the exterior walls or roof of a building and employed to heat a fluid, such as air or water, which may subsequently be distributed throughout the building. Such solar energy collectors generally comprise a glazing or transparent cover panel which permits the passage of a substantial portion of solar energy and a solar energy absorbing element. The cover panel and energy absorbing element are generally held in spaced relation by other structural members of the collector to permit passage therethrough of a fluid, such as air or water, to be heated in the collector and then distributed, directly or indirectly, for heat transfer within the building. The collector unit may be provided with means for fastening to the outside of the building or other structure to be heated thereby. In a typical location on the exterior of a building, such collectors are commonly exposed to considerable fluctuations in temperature. The collector is generally rigidly constructed and fastened to the building. Fluctuations in temperature cause expansion and contraction of material of the collector, commonly with a resultant distortion and/or loosening of the elements or members. In addition, since the various parts or members of the collector are commonly fabricated from different materials, having different thermal expansion characteristics, the resultant differential expansion and contraction may further increase such problems as the loosening of the various parts of the collector unit.
It is an object of this invention to provide a solar energy collector unit that is economical to fabricate, simple to install, and which provides improved resistance to deterioration from the effects of normal fluctuations in atmospheric temperatures. It is an additional object to provide a solar energy collector unit characterized by an interlocking non-rigidly attached glazing system which allows linear and lateral expansion of the glazing.